FunConnect/client/src/main/local-proxy.ts

import * as net from 'net';
import { RelayClient } from './relay-client';

export class LocalProxy {
  private server: net.Server | null = null;
  private connections: Set<net.Socket> = new Set();

  constructor(
    private port: number,
    private relayClient: RelayClient
  ) {}

  start(): Promise<void> {
    return new Promise((resolve, reject) => {
      this.server = net.createServer((clientSocket) => {
        this.connections.add(clientSocket);

        // Connect to relay for this MC client
        const relaySocket = this.relayClient.getSocket();
        if (!relaySocket || !this.relayClient.isConnected()) {
          clientSocket.destroy();
          return;
        }

        // Forward MC client data to relay
        clientSocket.on('data', (data) => {
          if (this.relayClient.isConnected()) {
            this.relayClient.write(data);
          }
        });

        // Forward relay data back to MC client
        this.relayClient.onData((data) => {
          if (!clientSocket.destroyed) {
            clientSocket.write(data);
          }
        });

        clientSocket.on('close', () => {
          this.connections.delete(clientSocket);
        });

        clientSocket.on('error', () => {
          this.connections.delete(clientSocket);
        });
      });

      this.server.on('error', (err) => {
        reject(err);
      });

      this.server.listen(this.port, '127.0.0.1', () => {
        console.log(`[LocalProxy] Listening on 127.0.0.1:${this.port}`);
        resolve();
      });
    });
  }

  stop(): void {
    for (const conn of this.connections) {
      conn.destroy();
    }
    this.connections.clear();
    if (this.server) {
      this.server.close();
      this.server = null;
    }
  }

  getPort(): number {
    return this.port;
  }

  getConnectionCount(): number {
    return this.connections.size;
  }
}